Finding the Fourth Proportional to 518,447, 715,456.89 and 279,983

Step by Step Solution

1. Step 1: Write the proportion equation
   518,447 : 715,456.89 = 279,983 : x
2. Step 2: Convert to fraction form
   518,447/715,456.89 = 279,983/x
3. Step 3: Cross multiply
   518,447x = 715,456.89 × 279,983
4. Step 4: Simplify right side
   518,447x = 200,315,766,432.87
5. Step 5: Solve for x
   x = 200,315,766,432.87/518,447
6. Step 6: Final answer
   x = 386,376.56